The invention pertains to electric motor apparatus, and particularly pertains to low cost low voltage motor units and multiple motor assemblies concisely interrelated.
12 volt electric motors of fractional horsepower are widely used in automotive applications for window regulation and seat adjustment purposes, and such motors must be capable of producing relatively high torque, reversible, dependable in operation, and concise in size and construction since such motors are mounted in door panels and under-seat installations. Vehicle electric seats permit reversible vertical adjustment of the front and rear seat portions as well as a traversing adjustment in the direction of the vehicle length, and such electric seat mechanisms, in the past, have been powered by a plurality of electric motors, usually three. Such plural seat adjustment motors have been incorporated into a concise multiple armature arrangement as shown in U.S. Pat. Nos. 3,365,163 and 3,437,303 wherein three armatures are located within a specially designed motor housing in parallel side-by-side relationship.
In the aforementioned patents the construction of such a multiple motor assembly is expensive as the motor casing and end caps are specially formed by metal castings for the particular application.
Electric motor constructions using sheet metal casings normally employ casings formed of special tubing or wherein the casing is formed of a formed sheet metal blank, second operations, such as welding, are required to maintain the final casing configuration. Prior sheet metal formed motor casings are difficult to accurately form and require expensive assembly techniques.